Results 1 to 10 of about 54,073 (249)

Diastereoselectivity in the Staudinger reaction of pentafluorosulfanylaldimines and ketimines

Beilstein Journal of Organic Chemistry, 2013
β-Lactams were diastereoselectively formed by the reaction of SF5-containing aldimines, or an SF5-containing ketimine, with benzyloxyketene in a conrotatory ring closure process. Imine formation and cyclization were possible in spite of the acidification
Alexander Penger, Cortney N. von Hahmann, Alexander S. Filatov, John T. Welch   +3 more
doaj   +2 more sources

Diastereodivergent electrophilic trapping of α-boryl lithium derivatives [PDF]

Beilstein Journal of Organic Chemistry
α-Boryl carbanions are valuable organoboron intermediates, but controlling their stereoselective reactions remains challenging. Here, we examine the diastereoselective generation and trapping of α-boryl lithium species formed by ring opening of ...
Tereza Pavlíčková, Noam Orbach, Ilan Marek   +2 more
doaj   +2 more sources

Iodine-promoted oxidative homocoupling of methyl 2-arylacetates under equilibrium conditions using potassium tert-butoxide as a base

Results in Chemistry, 2022
Iodine-promoted dimerization of enolates of methyl 2-arylacetates generated with tBuOK under equilibrium conditions are reported. The oxidative homocoupling reaction furnishes a mixture of dl and meso dimers in moderate to good yields and ...
Ahmed Y. Nuriye, Joseph Barr
doaj   +1 more source

Controlling Enantioselectivity and Diastereoselectivity in Radical Cascade Cyclization for Construction of Bicyclic Structures

Journal of the American Chemical Society, 2021
Radical cascade cyclization reactions are highly attractive synthetic tools for the construction of polycyclic molecules in organic synthesis. While it has been successfully implemented in diastereoselective synthesis of natural products and other ...
Congzhe Zhang, Duo-Sheng Wang, W. Lee, Alexander M. McKillop, X. Zhang   +4 more
semanticscholar   +1 more source

Regio- and Diastereoselective Vicinal Aminobromination of Electron Deficient Olefins via Phosphorus-Based GAP Protocol

Frontiers in Chemistry, 2021
Chemical synthesis based on Group-Assisted Purification chemistry (GAP) has been prolifically used as a powerful, greener and ecofriendly tool so far. Herein, we report hypervalent iodine (III) mediated regio- and diastereoselective aminobromination of ...
Anis Ur Rahman, Nighat Zarshad, Iltaf Khan, Faisal Faiz, Guigen Li, Guigen Li, Asad Ali   +6 more
doaj   +1 more source

An Approach toward 17-Arylsubstituted Marginatafuran-Type Isospongian Diterpenoids via a Palladium-Catalyzed Heck–Suzuki Cascade Reaction of 16-Bromolambertianic Acid

Molecules, 2022
Isospongian diterpenes are a small but growing family of natural tetracyclic secondary metabolites isolated from marine organisms, primarily sponges and nudibranchs.
Yurii V. Kharitonov, Elvira E. Shults
doaj   +1 more source

Temperature-Controlled Diastereoselective Doebner/Ugi Tandem Reaction

SynOpen, 2023
Novel peptidomimetics containing a pyrrolone fragment were synthesized by a tandem combination of Doebner and Ugi type multicomponent reactions with controlled diastereoselectivity. This approach represents a convenient synthesis in the temperature range
Yana Sakhno, Oleksandr Radchenko, Vyacheslav Saraev, Yuliia Shliapkina, Mariia Kaidash, Mariia Shyshkina, Svitlana Shishkina, Vladimir Musatov, Sergey Desenko, Valentyn Chebanov   +9 more
doaj   +1 more source

Synthesis of the [11]Cyclacene Framework by Repetitive Diels–Alder Cycloadditions

Molecules, 2021
The Diels–Alder cycloaddition between bisdienes and bisdienophile incorporating the 7-oxa-bicyclo[2.2.1]heptane unit are well known to show high diastereoselectivity that can be exploited for the synthesis of molecular belts. The related bisdiene 5,6,7,8-
John B. Bauer, Fatima Diab, Cäcilia Maichle-Mössmer, Hartmut Schubert, Holger F. Bettinger   +4 more
doaj   +1 more source

Diastereoselective Cascade Cyclization of Diazoimides with Alkylidene Pyrazolones for Preparation of Pyrazole-Fused Oxa-Bridged Oxazocines

Molecules, 2023
Under the catalysis of Rh2(OAc)4 (10 mol%) and binapbisphosphine ligand (±)-L3 (20 mol%) in DCE at 80 °C, the cascade cyclization of diazoimides with alkylidenepyrazolones underwent stereoselectively (dr > 20:1), affording pyrazole-fused oxa-bridged ...
Kuo Wang, Yue Zhang, Lu-Yu Cai, Xiu-Qing Song, Chen Wang, Jia-Rui Zhang, Yi-Fan Pan, Hong-Wu Zhao   +7 more
doaj   +1 more source

Studies on the Synthesis of DMAP Derivatives by Diastereoselective Ugi Reactions

Molecules, 2011
Diastereoselective Ugi reactions of DMAP-based aldehydes with α-amino acids and tert-butyl isocyanide were examined. The reactions of 4-(dimethylamino)-2-pyridine-carboxaldehyde with various α-amino acids afforded 2-substituted DMAP derivatives with low ...
Koichi Mitsudo, Seiji Suga, Hiroki Mandai, Shunsuke Irie   +3 more
doaj   +1 more source